US3882482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical radiant energy encoding and correlating apparatus
Assignee: Unisys Corp
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Filing: 1969-09-12
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Granted: 1975-05-06
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Expires: 1989-09-12
Abstract
Abstract Object locating apparatus including receiver optics for focussing optical radiant energy emitted from an object within its field of view onto a rotatable drum having a plurality of pseudo-random coded sections disposed along a continuous loop track, the code pattern in alternate sections being identical while those in adjacent sections are skewed and inverted relative to one another. Rotation of the drum uniquely encodes the radiant energy in accordance with its position thereon and a photodetector converts the encoded energy to an equivalent electrical signal preparatory to correlation with a reference code for a period equal to the time required for two of the drum sections to pass through the field.
Inventors
- 👤 Benjamin W Green
- 👤 Richard E Roble
- 👤 Irving Roth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:37
CPC Classifications
G; G01; G01S; G01S3/00; G01S3/78; G01S3/782; G01S3/783; G01S3/7835; G01S3/781
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
105 words
An optical encoder comprising a member having a continuous loop track including at least two coded sections each having a plurality of bands disposed along the track with each band containing the same pseudo-random code formed by means of segments respectively relatively more transparent and opaque to optical radiant energy, the transmissivity of the code segments in one section being inverted with respect to the corresponding code segments in the other section and the codes in the bands of at least one of the sections being shifted relative to one another whereby the code patterns of the respective sections are skewed relative to one another.
Claim 2
Dependent Claim
105 words
An optical encoder comprising a member having a continuous loop track including at least two coded sections each having a plurality of bands disposed along the track with each band containing the same pseudo-random code formed by means of segments respectively relatively more transparent and opaque to optical radiant energy, the transmissivity of the code segments in one section being inverted with respect to the corresponding code segments in the other section and the codes in the bands of at least one of the sections being shifted relative to one another whereby the code patterns of the respective sections are skewed relative to one another.
Claim 3
Dependent Claim
25 words
The apparatus of claim 1 wherein corresponding code segments in each band of the respective sections are located at different relative positions within the sections.
Claim 4
Dependent Claim
51 words
The apparatus of claim 1 wherein the code in each band of one section is shifted with respect to the code in respective collinearly aligned bands of the other section and the number of bands in each section is at least one less than the number of segments in the codE.
Claim 5
Dependent Claim
66 words
The apparatus of claim 2 wherein the code in each band of one coded section is shifted by a different discrete amount in one direction along the track with respect to the code in one of the bands in said one code section and the codes in the corresponding bands of the other section are shifted by similar amounts in the opposite direction along the track.
Claim 6
Dependent Claim
30 words
The apparatus of claim 2 wherein the continuous loop track includes additional coded sections disposed in contiguous relationship around the track and the code patterns are identical in alternate sections.
Claim 7
Dependent Claim
112 words
The apparatus of claim 5 further comprising optical means positioned adjacent said member for focussing energy radiated from an object in its field of view onto the continuous loop track within an area equal to the areal dimensions of a coded section, means for moving said member such that the coded sections successively pass through the focal plane of the optical means to encode the energy incident thereon with a period equal to the length of time required for two coded sections to pass therethrough, and a photodetector positioned relative to said member to receive the encoded energy transmitted through the coded sections and convert it to an equivalent encoded electrical signal.
Claim 8
Dependent Claim
29 words
The apparatus of claim 6 further comprising a condenser lens positioned intermediate the coded sections and the photodetector to collect the encoded energy and direct it onto the photodetector.
Claim 9
Dependent Claim
53 words
The apparatus of claim 6 in combination with a reference code generator for prepetitively generating a reference code which is an electrical phase shifted replica of the pseudo-random code formed in each band of one set of the alternate coded sections, and means for correlating the reference code and the encoded electrical signal.
Claim 10
Dependent Claim
59 words
The apparatus of claim 8 wherein the correlation period is equal to the period of the encoded electrical signal and the reference code generator comprises means for shifting the reference code one bit in a prescribed direction as each bit of the encoded signal is generated, and further including means for synchronizing the reference code with the encoded signal.
Claim 11
Dependent Claim
78 words
The apparatus of claim 9 wherein the correlating means includes a plurality of coincidence detectors and a plurality of integrators, each integrator being connected to the output terminals of a corresponding coincidence detector which operates to determine similarity and dissimilarity of the synchronous reference code and encoded electrical signal bits applied to its input terminals and the totality of coincidence detectors being equal in number to the number of code segments in each band of a coded section.
Claim 12
Dependent Claim
45 words
The apparatus of claim 9 and further including means for delaying for at least one encoding period the encoded electrical signal generated during one period, and means for subtractively combining the delayed encoded electrical signal and the encoded electrical signal generated during a subsequent period.
Claim 13
Dependent Claim
36 words
The apparatus of claim 11 and further including a filter responsive to the slope of the leading edge of the envelope of the encoded electrical signal for providing a trigger signal to actuate the delay means.
References Cited (Backward Citations)
US3216004A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |